The present invention relates to a cutting device for continuous rods of smoking products.
In particular, the present invention relates to a cutting device for continuous rods of cigarette, of the type comprising a blade carrier head rotatable about an axis substantially parallel to a direction of advancement of the said rod and provided with at least one so-called `helical` blade extending radially outwardly of the blade carrier head itself. Upon each rotation of this latter, each blade is sharpened by at least one grinding wheel of frustoconical form carried by a wheel-carrier head rotatable in phase with the blade carrier head about an axis substantially perpendicular to the axis of rotation of the blade carrier head itself. In known cutting devices of the above described type the said grinding wheel or stone is mounted eccentrically on the associated head for the purpose of being able to perform, following each rotation of the grinding wheel carrier head about its own axis, a displacement having a component parallel to the axis of the blade carrier head. The grinding wheel is in this way capable of following a path such as to come successively into contact with every point on the cutting edge of the blade to be sharpened.
In such cutting devices the blade carrier head is normally adjustable for the purpose of being able to adapt the cut to cigarettes of different size. This adjustment normally comprises a variation of the inclination of each blade with respect to the axis of the blade carrier head, with a consequent variation in the path of the points of the cutting edge of each blade. Consequently, the law of displacement of the grinding wheel must be modified by varying the eccentricity with respect to the axis of the grinding wheel carrier head.
For the purpose of being able to achieve what has been described above, in known cutting devices, it has been necessary to face and resolve several constructional problems such as those concerning the formation of a device for adjusting the eccentricity of each grinding wheel so as to maintain the grinding wheel carrier head perfectly balanced and to permit the transmission to the grinding wheel of a rotary movement about its axis whatever the position of the grinding wheel on the grinding wheel carrier head.
In known cutting devices the problems described above are resolved by providing the grinding wheel carrier head with a certain number of interchangeable pieces selectively mountable on the grinding wheel carrier head itself upon variation in the size of the cigarette to be obtained. Obviously, such a solution significantly affects the cost of the grinding wheel carrier head and notably increases the working dead times.